Solar Coils that lay flat on roof

I am considering a solar pool heater that uses black coils filled with water that lay on top of the roof. I have a durolast roof that has really made a difference keeping my house cooler. I am concerned that the solar coils will bring additional heat back into the house. Does anyone have experience or thoughts on this?

I was wondering if you had any direct replies to your query. My situation is identiical--I'm considering solar heating for my pool. It would be composed of black tubing filled with water on a foam roof.

I expect, perhaps simplistically, that the roof insulation will still do its job even with the coil mounted. I haven't had the quote yet but was planning on asking for references (hopefully some would be Eichlers.)

I need to get more than one quote and was wondering if you would be willing to email me the name of the company you're dealing with.